The present invention relates to improvements in bagasse fiber preparation equipment, and more particularly to an improved method and apparatus for depithing bagasse fibers.
In the various fibers available for the making of paper, bagasse has been used for the fibrous content and the substantial volume of bagasse available as a residue of sugar cane, makes the relative economics desirable. A substantial impediment to the wide scale use of bagasse is the difficulty of depithing where the pith is separated from the fibers.
In the processing of sugar cane, the cane is crushed and processed to remove the sugar juice and the bagasse residue is then suitable for processing to obtain bagasse fibers for bagasse paper.
In processes heretofore available, bagasse has been depithed both by wet and dry processes. In both processes, the bagasse is generally mechanically abraded to break the clusters of pith away from the remaining tissue. Dry depithing has been accomplished by using a hammer mill followed by dry screening. The material losses of depithing are considerable and economics dictate that improved bagasse depithing processes are needed to improve the quality of the fibers and avoid loss as well as to reduce the actual costs of depithing.
In processes heretofore available, removal of pith from the fibers has not been fully thorough and traces of the pith remain in the fibers. Varieties in processing bagasse prior to preparing the bagasse fibers for paper by depithing will also vary providing challenges for the satisfactory removal of pith for the preparation of the bagasse fibers. A discussion of processes heretofore employed and the necessity of a substantial removal of nonfibrous constituents from bagasse fibers is discussed in an article entitled "Sugar Cane Bagasse As A Fibrous Papermaking Material", published by TAPPI, Vol. 40, No. 8, Aug. 1957.